In a most recent network, there is a service chain system in which, when an access is performed from the base location to an external site or when an access is performed from the base location to another base location, network (NW) functions, such as functions of a firewall (FW), a Proxy, and the like, are virtually arranged on communication paths in accordance with a request and then packets are transferred. A communication path passing through virtual NW functions is referred to as a service chain.
Conventionally, a NW function is operated in a physical NW device, such as a NW server, or the like. However, due to an improvement of the performance of recent general-purpose servers, the NW function is operated even in a software process in a general-purpose server. Accordingly, an operation of the NW function is started in the configuration in which a program of the NW function is operated in a virtual machine in a virtual environment of the general-purpose server. Furthermore, the software process related to a NW that is operated in a virtual machine is referred to as a virtual network function (virtual NW function: VNF).
However, the operation mode of a process related to a NW, such as data transfer or the like, is shifted from a physical NW device to a VNF that is performed by the software process in the general-purpose server and, consequently, a state of a decrease in the process performance of the data transfer occurs. Thus, by executing a plurality of programs in parallel, by operating and scaling out virtual machines in parallel in a plurality of servers, the load of data transfer is distributed and the process performance of the data transfer is improved.
FIG. 30 is a schematic diagram illustrating an example of the arrangement configuration of a service chain. A service chain 200 illustrated in FIG. 30 arranges, for example, each of VNFs 201, such as FWs 201A, Intrusive Detection Systems (IDSs) 201B, Proxies 201C, and the like. Furthermore, the service chain 200 arranges Load Balancers (LB) 202 that distribute the traffic load to each of the VNFs 201 in a previous stage. The LBs 202 distribute the load (traffic) to each of the VNFs 201 arranged in the next stage. Consequently, by distributing the load applied to the transfer process of each of the VNFs 201, a decrease in the process performance due to software implementation is suppressed.
Patent Document 1: Japanese Laid-open Patent Publication No. 2014-225157
Patent Document 2: Japanese Laid-open Patent Publication No. 2014-21854
However, in the VNFs 201 that constitute the service chain 200, the LB 202 is needed for each of the VNFs 201 and thus a transfer delay occurs every time a process passes each of the LBs 202. Furthermore, because the service chain 200 needs a lot of the LBs 202, the resources in the virtual area in the general-purpose servers are consequently used.